Well, it is a bit difficult to understand if you don't practice. I think you really need to start using these things in your code and make your own experiments to really grasp them. Once you get a working knowledge on them, you'll probably wonder how you could live without them before.

If you're interesting in digging into these techniques further, please read this excellent book: https://hop.perl.plover.com/book/ by dominus. You can read it for free on-line, but I should warn you that you might end up willing to buy the paper copy. At least, that's what happen to me when I first read it about ten years ago.